Global Information Lookup Global Information

Fraction of absorbed photosynthetically active radiation information


The fraction of absorbed photosynthetically active radiation (FAPAR, sometimes also noted fAPAR or fPAR) is the fraction of the incoming solar radiation in the photosynthetically active radiation spectral region that is absorbed by a photosynthetic organism, typically describing the light absorption across an integrated plant canopy.

This biophysical variable is directly related to the primary productivity of photosynthesis and some models use it to estimate the assimilation of carbon dioxide in vegetation in conjunction with the leaf area index. FAPAR can also be used as an indicator of the state and evolution of the vegetation cover; with this function, it advantageously replaces the Normalized Difference Vegetation Index (NDVI), provided it is itself properly estimated.

FAPAR can be directly measured on the ground, by putting a spectrometer above and below canopy cover. On a larger scale, however, it is estimated from space measurements in the solar spectral range and a number of state of the art algorithms have been proposed to derive this important environmental variable.[1] Currently, there are some remote sensing products of FAPAR, such as AVHRR and MODIS.

FAPAR is one of the 50 Essential Climate Variables recognized by the UN Global Climate Observing System (GCOS) as necessary to characterize the climate of the Earth. GCOS has issued specific recommendations to monitor this variable systematically, both through a reanalysis of existing databases and in the future with current and forthcoming instruments.

  1. ^ Qin, Haiming; Wang, Cheng; Zhao, Kaiguang; Xi, Xiaohuan (29 May 2018). "Estimation of the fraction of absorbed photosynthetically active radiation (fPAR) in maize canopies using LiDAR data and hyperspectral imagery". PLOS ONE. 13 (5): e0197510. Bibcode:2018PLoSO..1397510Q. doi:10.1371/journal.pone.0197510. PMC 5973554. PMID 29813094.

and 28 Related for: Fraction of absorbed photosynthetically active radiation information

Request time (Page generated in 0.8852 seconds.)

Fraction of absorbed photosynthetically active radiation

Last Update:

fraction of absorbed photosynthetically active radiation (FAPAR, sometimes also noted fAPAR or fPAR) is the fraction of the incoming solar radiation in...

Word Count : 308

Photosynthetically active radiation

Last Update:

Photosynthetically active radiation (PAR) designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic...

Word Count : 2772

Normalized difference vegetation index

Last Update:

plants absorb solar radiation in the photosynthetically active radiation (PAR) spectral region, which they use as a source of energy in the process of photosynthesis...

Word Count : 3621

Photosynthetic efficiency

Last Update:

what kind of light is used (see Photosynthetically active radiation). It takes eight (or perhaps ten or more) photons to use one molecule of CO2. The Gibbs...

Word Count : 2455

Vegetation index

Last Update:

Index Weighted Difference Vegetation Index (WDVI) Fraction of absorbed photosynthetically active radiation (FAPAR) Normalised Difference Greenness index (NDGI)...

Word Count : 1747

Photosynthesis

Last Update:

Organic reaction Photobiology Photoinhibition Photosynthetic reaction center Photosynthetically active radiation Photosystem Photosystem I Photosystem II Quantasome...

Word Count : 11577

Photoacoustic effect

Last Update:

conversion of the absorbed pulsed or modulated radiation into heat energy. temporal changes of the temperatures at the loci where radiation is absorbed – rising...

Word Count : 3887

Fluorescence

Last Update:

Fluorescence is one of two kinds of emission of light by a substance that has absorbed light or other electromagnetic radiation. Fluorescence involves...

Word Count : 10628

Oxygen

Last Update:

by the photosynthetic action of living organisms. Another form (allotrope) of oxygen, ozone (O 3), strongly absorbs ultraviolet UVB radiation and the...

Word Count : 11768

Radiocarbon dating

Last Update:

pathways 12 C is absorbed slightly more easily than 13 C, which in turn is more easily absorbed than 14 C. The differential uptake of the three carbon...

Word Count : 13848

Space habitat

Last Update:

and thus has a much smaller mass-fraction than in other concepts. For a long-term habitation, however, radiation shielding must rotate with the habitat...

Word Count : 4472

Cyanobacteria

Last Update:

of the Earth", which dramatically changed the composition of life forms on Earth. Cyanobacteria use photosynthetic pigments, such as various forms of...

Word Count : 17513

Fermi paradox

Last Update:

{\displaystyle f_{i}} , the fraction of life-bearing planets whereon intelligent life appears; f c {\displaystyle f_{c}} , the fraction of civilizations that reach...

Word Count : 14183

Phytoplankton

Last Update:

fluxes as well as the transfer and cycling of organic matter via biological processes. The photosynthetically fixed carbon is rapidly recycled and reused...

Word Count : 6484

Habitability of red dwarf systems

Last Update:

cap. Further research—including a consideration of the amount of photosynthetically active radiation—suggested that tidally locked planets in red dwarf...

Word Count : 6389

Carbon dioxide

Last Update:

In the air, carbon dioxide is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. Carbon dioxide is soluble in water...

Word Count : 12908

Ozone depletion

Last Update:

affected by radiation throughout development are more affected by the inability to intercept light with a larger leaf area than having photosynthetic systems...

Word Count : 15733

Theoretical production ecology

Last Update:

cannot process them swiftly enough. Light – Light, also called photosynthetic Active Radiation (PAR) is the energy source for green plant growth. PAR powers...

Word Count : 2043

Antioxidant

Last Update:

of active ingredients and lipid content. For example, phenolic antioxidants such as stilbenes, flavonoids, and hydroxycinnamic acid strongly absorb UV...

Word Count : 10076

DNA repair

Last Update:

factors such as radiation can cause DNA damage, resulting in tens of thousands of individual molecular lesions per cell per day. Many of these lesions cause...

Word Count : 15713

Dissolved organic carbon

Last Update:

Dissolved organic carbon (DOC) is the fraction of organic carbon operationally defined as that which can pass through a filter with a pore size typically...

Word Count : 9614

Glossary of environmental science

Last Update:

effect; gaseous constituents of the atmosphere, both natural and from human activity, that absorb and re-emit infrared radiation. Water vapor (H2O) is the...

Word Count : 16935

Naturally occurring phenols

Last Update:

The absorbance pattern responsible for the red color of anthocyanins may be complementary to that of green chlorophyll in photosynthetically active tissues...

Word Count : 7807

EXPOSE

Last Update:

significant fraction of protons of the radiation belts and solar wind did not reach the samples. R3D measured ionizing and non-ionizing radiation as well...

Word Count : 7283

Photocatalytic water splitting

Last Update:

carbon dioxide into oxygen and carbohydrates. Water splitting using solar radiation has not been commercialized. Photocatalytic water splitting is done by...

Word Count : 3825

Nannochloropsis and biofuels

Last Update:

productivity of the algae also peaked under blue light for both cultures. In another study, UV-A (320 - 400 nm) was added to the photosynthetically active light...

Word Count : 1973

Planetary habitability

Last Update:

cap. Further research—including a consideration of the amount of photosynthetically active radiation—suggested that tidally locked planets in red dwarf...

Word Count : 13242

Biology

Last Update:

initial step of photosynthesis whereby light energy is absorbed by chlorophyll pigments attached to proteins in the thylakoid membranes. The absorbed light energy...

Word Count : 13782

PDF Search Engine © AllGlobal.net